Abstract
This invention relates to the single step conversion of ethanol and/ or aldehydes (i.e. acetaldehyde, butyraldehydes, crotonaldehyde) (either aqueous or neat) to 1- and 2-butenes-rich olefins. 1-Butene itself a commodity chemical can be converted into polybutene, its main application is as a comonomer in the production of certain kinds of polyethylene, such as linear low-density polyethylene (LLDPE). 1-Butene has also been used as a precursor to polypropylene resins, butylene oxide, and butanone. Mixtures of 1-butene and 2-butene, as produced by the methods disclosed in this invention, can be oligomerized and hydrogenated into gasoline, jet, and diesel fuels and/or into valuable fuel additives and lubricants. For the current alcohol-to-jet process, producing 1- and 2-butene from ethanol is performed in two separate steps by first dehydrating ethanol into ethylene and then dimerizing e thylene into 1- and 2-butene in a second step. Here we disclose the methods for producing 1- and 2-butene mixtures directly from either ethanol, acetaldehyde, butyraldehyde, corotonaldehyde or mixture of ethanol with one of these aldehydes. This is done using specially tailored polyfunctional catalysts comprising metal component with relatively weak hydrogenation ability (e.g., Cu) with mildly acidic support materials (e.g., ZrO2 supported on SiO2). In previous work, including a separate patent, we demonstrated such catalytic materials to be active for converting ethanol into 1,3-butadiene in one reactor. In a separate patent, we demonstrated supported Ag catalysts to be active for (aqueous) ethanol conversion into a mixture of 1 and 2-butenes. Direct conversion of aldehydes or mixture of aldehydes and ethanol into 1 and 2-butenes rich olefins has not been reported before. In this disclosure, we report these catalysts to be active and selective for converting ethanol and/ or aldehydes to 1- and 2-butenes in one single reactor under mild reducing conditions (e.g., under H2, T = 400 degrees C, P = 7 bar). Furthermore, catalyst formulation (i.e. effect of the nature of the support, promoters addition, Cu loading and ZrO2 loading) and process parameters such as H2 concentration, ethanol partial pressure, space velocity were demonstrated to have significant effect on conversion, selectivity, and stability. Results are shown in separate word document with experimental data included in Tables and Figures Here we also demonstrate how catalytic stability is enhanced for the Cu-based catalyst as compared to the Ag-based catalyst. The Cu-based catalyst presents higher resistance to coking and oxidation which enables superior durability. The product from the ethanol and or aldehyde(s) conversion contains primarily butenes and ethylene olefins mixed with H2. We previously demonstrated in a separate patent how these butenes-rich olefins can be oligomerized into gasoline, jet, diesel range hydrocarbons.
Application Number
17/846,476
Inventors
Dagle,Vanessa
Dagle,Robert A
Market Sector
Environmental
Energy Production and Efficiency
Chemistry and Catalysts
Biological Sciences and Omics